Field
The present disclosure relates to a tactile sensor, and more particularly, to a tactile sensor that not only has flexibility and elasticity, but also requires a reduced number of wires to be used for sending and receiving signals, and is thereby easy to manufacture and saves costs.
Description of Related Art
Recently, as industrial technologies develop, there are active efforts to develop industrial robots and medical robots as tools capable of carrying out dangerous operations and detailed operations instead of human beings.
At the early stages of development, these robots were designed to perform simple operations repeatedly, but recently, there is a demand to develop intelligent robots of evolved forms equipped with the appearance, thoughts and even behaviors of human beings such as humanoids so that they can gradually perform more complicated operations.
In the case of the aforementioned intelligent robots, since it its practically impossible for designers to input all the operation programs for coping with every external situation one by one, the robots are required to recognize and determine the external environment (or stimulation) for themselves using their sensors that are similar to the sensory organs of human beings, and to behave accordingly.
One of the most important technologies related to these intelligent robots is the technology of tactile sensors or contact sensors capable of sensing the size, contacting position and the like of the external load contacting the intelligent robot.
Capacitor type sensors are one type of conventional tactile sensors. Capacitor type sensors are configured in the form of a general capacitor where a dielectric is disposed between an anode and a cathode. Thus, when the dielectric is deformed by an external stimulation, a change in capacitance occurs, and thus the external stimulation can be sensed using this change in capacitance.
However, conventional tactile sensors have limitations in reducing their thickness, and another problem is that the durability of the electrodes contacting external elements cannot be secured. Further, when sensing an external stimulation, in an automatic control, due to the electrode exposed towards outside, a disturbance may occur that can cause a change in the amount of control besides the reference input. Further, since wires are required as many as the number of cells in order to connect the anode and cathode in each cell (the minimum unit forming a group of anode and cathode) that constitutes the sensor, it is difficult and complicated to manufacture the sensor, which is a disadvantage.
Therefore, there is an emerging demand for a tactile sensor that compensates the aforementioned problems.